/* roulang page: index */
:root {
      --primary: #0D3B2E;
      --primary-light: #165B48;
      --accent-emerald: #10B981;
      --accent-amber: #F59E0B;
      --bg-light-1: #F8FAFC;
      --bg-light-2: #F1F5F9;
      --dark-obsidian: #071914;
      --text-main: #0F172A;
      --text-muted: #475569;
      --text-soft: #64748B;
      --border-line: #E2E8F0;
      --card-radius: 10px;
      --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.04);
      --shadow-md: 0 6px 20px -2px rgba(13, 59, 46, 0.08);
      --shadow-hover: 0 12px 28px -4px rgba(13, 59, 46, 0.14);
      --transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
    }

    * { box-sizing: border-box; }
    body {
      font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      color: var(--text-main);
      background-color: var(--bg-light-1);
      line-height: 1.65;
      margin: 0;
      padding: 0;
      -webkit-font-smoothing: antialiased;
    }
    a { text-decoration: none; color: inherit; transition: var(--transition); }
    img { max-width: 100%; height: auto; display: block; }

    /* Top Sub-bar */
    .top-sub-bar {
      background-color: #08261E;
      color: #94A3B8;
      font-size: 0.82rem;
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .top-sub-bar a { color: #CBD5E1; }
    .top-sub-bar a:hover { color: var(--accent-emerald); }

    /* Main Navigation */
    .main-navbar {
      background-color: rgba(255, 255, 255, 0.96);
      border-bottom: 1px solid var(--border-line);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .main-navbar.sticky-nav {
      backdrop-filter: blur(8px);
      -webkit-backdrop-filter: blur(8px);
    }
    .navbar-brand-text {
      font-weight: 800;
      font-size: 1.25rem;
      letter-spacing: -0.5px;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .nav-link {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-muted) !important;
      padding: 0.5rem 0.9rem !important;
    }
    .nav-link:hover, .nav-link.active {
      color: var(--primary) !important;
      font-weight: 600;
    }

    /* Common Components */
    .section-wrap {
      padding: 85px 0;
      position: relative;
    }
    .bg-canvas-1 { background-color: var(--bg-light-1); }
    .bg-canvas-2 { background-color: var(--bg-light-2); }
    .bg-dark-obsidian {
      background-color: var(--dark-obsidian);
      color: #E2E8F0;
    }
    .section-tag {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      font-size: 0.8rem;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.8px;
      padding: 4px 12px;
      border-radius: 20px;
      margin-bottom: 14px;
    }
    .tag-emerald { background: rgba(16, 185, 129, 0.12); color: #059669; }
    .tag-amber { background: rgba(245, 158, 11, 0.14); color: #B45309; }
    .tag-dark { background: rgba(255, 255, 255, 0.1); color: var(--accent-emerald); }

    .section-h2 {
      font-size: 2.15rem;
      font-weight: 800;
      line-height: 1.28;
      letter-spacing: -0.02em;
      margin-bottom: 16px;
    }
    .section-lead {
      color: var(--text-soft);
      font-size: 1.05rem;
      line-height: 1.7;
      max-width: 780px;
      margin-left: auto;
      margin-right: auto;
      margin-bottom: 45px;
    }
    .section-lead-start {
      color: var(--text-soft);
      font-size: 1.05rem;
      line-height: 1.7;
      max-width: 680px;
      margin-bottom: 30px;
    }

    .btn-action-primary {
      background-color: var(--primary);
      color: #FFFFFF;
      font-weight: 600;
      padding: 12px 26px;
      border-radius: 8px;
      border: 1px solid var(--primary);
      box-shadow: 0 4px 12px rgba(13, 59, 46, 0.2);
    }
    .btn-action-primary:hover {
      background-color: var(--primary-light);
      color: #FFFFFF;
      transform: translateY(-2px);
    }
    .btn-action-amber {
      background-color: var(--accent-amber);
      color: #1E293B;
      font-weight: 700;
      padding: 12px 26px;
      border-radius: 8px;
      border: none;
      box-shadow: 0 4px 12px rgba(245, 158, 11, 0.25);
    }
    .btn-action-amber:hover {
      background-color: #D97706;
      color: #FFFFFF;
      transform: translateY(-2px);
    }
    .btn-action-ghost {
      background-color: transparent;
      color: var(--primary);
      font-weight: 600;
      padding: 12px 24px;
      border-radius: 8px;
      border: 1px solid var(--border-line);
    }
    .btn-action-ghost:hover {
      background-color: rgba(13, 59, 46, 0.05);
      border-color: var(--primary);
      color: var(--primary);
    }

    .ui-card {
      background: #FFFFFF;
      border: 1px solid var(--border-line);
      border-radius: var(--card-radius);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      height: 100%;
    }
    .ui-card:hover {
      border-color: #CBD5E1;
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }

    /* Hero Section */
    .hero-container {
      background-image: linear-gradient(rgba(13, 59, 46, 0.88), rgba(7, 25, 20, 0.94)), url('/assets/images/f9743f55bbcdfb74.webp');
      background-size: cover;
      background-position: center;
      color: #FFFFFF;
      padding: 90px 0 100px;
      position: relative;
    }
    .hero-h1 {
      font-size: 2.85rem;
      font-weight: 800;
      line-height: 1.22;
      letter-spacing: -0.03em;
      margin-bottom: 20px;
    }
    .hero-intro {
      font-size: 1.15rem;
      color: #CBD5E1;
      line-height: 1.75;
      margin-bottom: 34px;
    }
    .group-buying-card {
      background: rgba(255, 255, 255, 0.07);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border: 1px solid rgba(255, 255, 255, 0.18);
      border-radius: 12px;
      padding: 30px;
      box-shadow: 0 12px 36px rgba(0,0,0,0.25);
    }
    .progress-bar-custom {
      height: 10px;
      border-radius: 5px;
      background: rgba(255, 255, 255, 0.2);
    }
    .progress-fill {
      background: linear-gradient(90deg, var(--accent-emerald), var(--accent-amber));
      height: 100%;
      border-radius: 5px;
    }

    /* Tab Custom */
    .nav-pills-custom .nav-link {
      background: #FFFFFF;
      border: 1px solid var(--border-line);
      border-radius: 8px;
      color: var(--text-main) !important;
      font-weight: 600;
      margin-bottom: 12px;
      padding: 14px 18px !important;
      text-align: left;
    }
    .nav-pills-custom .nav-link.active {
      background-color: var(--primary) !important;
      color: #FFFFFF !important;
      border-color: var(--primary);
      box-shadow: var(--shadow-md);
    }

    /* Accordion */
    .accordion-flush .accordion-item {
      border: 1px solid var(--border-line);
      border-radius: 8px;
      margin-bottom: 14px;
      background: #FFFFFF;
      overflow: hidden;
    }
    .accordion-button {
      font-weight: 700;
      font-size: 1.05rem;
      color: var(--text-main);
      padding: 18px 22px;
    }
    .accordion-button:not(.collapsed) {
      color: var(--primary);
      background-color: rgba(13, 59, 46, 0.04);
      box-shadow: none;
    }
    .accordion-body {
      padding: 18px 22px 24px;
      color: var(--text-muted);
      line-height: 1.7;
    }

    /* Fixed conversion bar */
    .sticky-bottom-action {
      position: fixed;
      bottom: 0;
      left: 0;
      right: 0;
      background: rgba(255, 255, 255, 0.98);
      border-top: 1px solid var(--border-line);
      box-shadow: 0 -4px 16px rgba(15, 23, 42, 0.08);
      z-index: 1020;
      padding: 10px 0;
    }

    /* Footer */
    .footer-base {
      background-color: #061511;
      color: #94A3B8;
      padding: 70px 0 90px;
      border-top: 1px solid rgba(255,255,255,0.06);
    }
    .footer-heading {
      color: #F8FAFC;
      font-size: 1rem;
      font-weight: 700;
      margin-bottom: 20px;
    }
    .footer-links li {
      margin-bottom: 10px;
      font-size: 0.9rem;
    }
    .footer-links a:hover {
      color: var(--accent-emerald);
    }

    @media (max-width: 991.98px) {
      .hero-h1 { font-size: 2.2rem; }
      .section-h2 { font-size: 1.8rem; }
      .section-wrap { padding: 60px 0; }
    }
    @media (max-width: 767.98px) {
      .hero-h1 { font-size: 1.85rem; }
      .sticky-bottom-action { display: none; }
      .footer-base { padding-bottom: 35px; }
    }